Anyone who wants to write about the constitutional crisis unfolding in the United States today faces a peculiar problem at the outset. There is a large body of observations that at one and the same time have been made too often and yet not often enough - too often because they have been repeated to the point of tedium for a minority ready to listen, but not often enough because the general public has yet to consider them seriously enough.

The problem for a self-respecting writer is that the act of writing almost in its nature promises something new. Repetition is not really writing but propaganda - not illumination for the mind but a mental beating. Here are some examples of the sort of observations I have in mind, at once over-familiar and unheard:

President George W Bush sent US troops into Iraq to find weapons of mass destruction (WMD), but they weren't there. He said Saddam Hussein's regime had given help to al-Qaeda, but it had not.

He therefore took the nation to war on the basis of falsehoods.

His administration says the torture at Abu Ghraib prison in Iraq and elsewhere has been the work of a few bad apples in the military, whereas in fact abuses were sanctioned at the highest levels of the executive branch in secret memos.

His administration lambastes leakers, but its own officials illegally leaked the name of a Central Intelligence Agency operative, Valerie Plame, to discredit her husband politically.

He flatly stated to the public that all wiretaps of Americans were ordered pursuant to court warrants, whereas in fact he was authorizing and repeatedly reauthorizing warrantless wiretaps. These wiretaps violated a specific law of Congress forbidding them.

His administration has asserted a right to imprison Americans as well as foreigners indefinitely without the habeas corpus hearings required by law.

Wars of aggression, torture, domestic spying and arbitrary arrest are the hallmarks of dictatorship, yet Congress, run by the president's party, has refused to conduct full investigations into either the false WMD claims, or the abuses and torture, or the warrantless wiretaps, or the imprisonment without habeas corpus.

When Congress passed a bill forbidding torture and the president signed it, he added a "signing statement" implying a right to disregard its provisions when they conflicted with his interpretation of his powers.